Overall, I'd say very nice work. The color of the red heart marble really does stand out and the lip shine draws my attention even more. Though there are many photos with things in people's mouths, this one has it's own little twist.
I personally like how it is zoomed really far, it gives more mystery to the emotion behind the words 'not said'. Great job on the lighting, gives the lips a shine as well as the marble ( though next time I'd recomend you somehow lessen the harshness of the glare ).
The vision is nice, great job experimenting, and it leaves me with a good feeling inside, yet wanting more..
You're lucky to have a sister who coorperates like that, mine would never do such a thing.